Honing machine



May 29, 1945. E. Y. s'EBoRG 2,377,272

HONING MACHINE Filed Sept. 13, 1943 l2 Sheets-Sheet 1 mj'. Karnes cSeboIC/IT-ro play-S' May 29, 1945. E. Y. sEBoRG HONING MACHINE Filed Sept.l5, 1945 2 Sheets-Sheet 2 OQ fromm@ L wv La I im 55km rsu MF I 53 SIZ* YI i LL "unan,

S? M52 le MR Eng-5I zzp-4, |51 mm ,21" 4 a2.

:al l .hw'l''n' 2.4 LI-S6 LS' a Nvs.. NTQ H J I {af-nest' ebor ,Q7/fi@Mind Patented May 29, 1945 HONING MACHINE IErarnest Y. Seborg, Rockford,Ill., assigner to Barnes Drill Co., Rockford, Ill., a corporation ofIllinois Application September 13, 1943, Serial No. 502,135

Claims.

The invention relates to machines for operating on cylindrical surfacesand more particularly to honing machines.

Both internal and external cylindrical surfaces are commonly finished bya honing operation in which a cylindrical abrasive tool or hone isrepeatedly traversed over the surface to be finished. As ischaracteristic of any abrasive operation, the iinished surface is markedby minute grooves corresponding to the paths followed by the individualabrasive particles of the tool.

While the grooves produced by the abrasive particles of honing tools areof microscopic size their orientation is an important factor indetermining the characteristics of the finished surface. In certainclasses of work, as for example, internal combustion engine cylinders asurface having helical grooves intersecting to produce a cross-hatcheffect is advantageous. A finish of this type is produced bycontinuously relatively rotating and simultaneously relativelyreciprocating the tool and work in predetermined timed relation.

For other types of Work, of which recoil and recuperator cylinders forgun carriages are an example, it is preferred that the grooves producedby the abrasive particles parallel the longitudinal axis of the work.This type of finish is produced by an operation commonly known aslapping or straight-line honing in which the tool and work arerelatively reciprocated axially without rotation. To prevent theabrasive particles from retracing the same paths, the tool and work areintermittently indexed that is, one or the other is rotated through arelatively small angle at one or both ends of the reciprocatory stroke.

One object of the invention is to provide an improved honing machine inwhich the tool and work may be relatively rotated continuously orindexed intermittently by the same prime mover.

Another object is to provide a novel system for controlling the spindledriving motor of a honing machine to adapt it for rotating the toolspindle continuously or indexing it in small, accurately measured stepsas required by the particular surface finish to be imparted to theworkpiece.

Other objects and advantages of the invention will become apparent fromthe following detailed description of the preferred embodimentillustrated in the accompanying drawings in which:

Figure 1 is a side elevational View of a honing machine embodying thefeatures of the invention.

Fig. 2 is a diagrammatic view of the tool supporting head of themachine.

Fig. 3 is a sectional view taken in a vertical plane substantially onthe line 3-3 of Fig. 1.

Fig. 4 is a circuit diagram of the electrical operating and controlcircuits of the machine.

For purposes of illustration the invention has been shown as applied toa horizontal honing machine of the type in which a cylindrical abrasivetool or hone H is rotated and simultaneously reciprocated in thecylindrical bore of a stationarily supported workpiece W. It will beunderstood, of course, that the invention may be incorporated in othertypes of honing machines. It is also to be understood that variouschanges and modifications in the form, construction and arrangement ofthe parts may be made without departing from the spirit and scope of theinvention as expressed in the appended claims. r

Referring to Fig. 1 of the drawings, the machine selected to illustratethe invention comprises generally an elongated base including a bedsection 5 and a 'work supporting section 6 bolted or otherwise rigidlysecured together in end-toend relation. Guide bars 1 (Fig. 3) mounted onthe side walls of the bed section in spaced parallel relation form ahorizontal track or guideway for a translatable tool supporting head 8.A spindle 9 journaled in the head is tted with an elongated tubulardriver I0 adapted to carry the hone H at its other end. The hone maythus be traversed axially through the workpiece W which is supported ona base section 6 by suitablefixvtures ll.

The hone H may be of the conventional expanding and contracting type andas herein shown is adapted to be expanded by a pressure fluid oper-'ated actuator. The actuator, in this instance, comprises a piston l5(Fig. 2) working in a cylinder I6 and connected by a rod Il withexpanding mechanism of well-known construction incorporated in the hone.Pressure iiuid is supplied to the closed end of the cylinder I6 by apump P driven by an electric motor M. A relief valve V l determines thepressure of the fluid supply to the cylinder while a conventionaltwo-position control valve actuated in any suitable manner as by asolenoid SO-l (Figs. 1 and 4) is arranged to connect the cylinderalternately with the pump and with a drain line i8 leading to a sump orreservoir R Within the head. Fluid is withdrawn from the reservoir bythe pump P through an intake line I9.

Upon delivery ofv fluid under pressure to the cylinder I6, the piston l5is forced outwardly or to the right as viewed in Fig. 2 to expand thewith resistors v4R. and 5R. The rswitch means as herein shown comprisesa conventional manually operable double pole switch S-3.- f

The resistors 4R and 5R maybe of any suitable character. lo insure asufiicientflow of current toenergize the relay, one resistor, in thisinstance the resistor 5R, is normally shunted by a switch R-ZB actuated'by the relay R-Z. When the relay is energizedgthe shunt is removedthereby increasing the resistance of the relay circuit to prevent therelay from overheating. A voltage responsive safety device 5l which maybe of any suitable and well-known type is arranged to open the relaycircuit and thus prevent damage to the relay in the event that-theswitch S-3 is improperlyset whenthe motor is operated at high voltage. ln

A second branch of the main supply line comprising conductors 52, 53 and54 supplies operating current to the head reciprocating motor M-I, thepump driving motor M, the honeyexpansion control solenoid vSO--I and thebrake solenoid SO-2. These conductors are connected and disconnectedfrom the supply line conductors by switches R--3l, R-32 and lib-33actuated by a control relay R-3.

Conductors 55 and 56 connect the conductor 52 and 53 directly with theconductor bars 40 and 4I for supplying current to the' pump motor M andthe brake solenoid SO-Z. The Contact members 34 and 35 coacting withthese conductor bars are connected directly with the motor M and,through the switches R-2I and R-22, with the solenoid SO-2.

Branch line conductor 54 is connected in a circuit including switchesMF-4 and MR-4 of the running relays MF and MR previously described, amanually operable selector switch 5 4, conductor bar 42, contact member36 and the hone expansion control solenoid SO-l. Thus with the switchS-4 set in one position the solenoid circuit is established' only whenboth motorsM-I and M2 are running, that is, when switches R,-3l, R-32and R-33 and one or the other of switches MF-4 or MR--A are closed. Withswitch S-4 set in its alternate position the solenoid circuit isswitched from the branch line conductor 54 to conductor 52 so that thesolenoid SO-l is energized when the motor M-l is running. The hone cantherefore be expanded for adjusting purposes or for straight line honingwhen the spindle 9 is not rotating. f

As shown in Fig. 4, the timer T and the control relays, with theexception of the relay R-Z, are connected in a low voltage controlcircuit and provided with conveniently accessible switches by which theoperating functions of the machine may be controlled. Current issupplied to the control circuit through a step-down transformer TFconnected with the main power line.

To place the machine in operation the head reciprocating motor M-l andthe pump driving motor M are started by momentary closure of a pushbutton actuated starting switch S-5.' Upon closure of this switch relayR-3 becomes lenergized and closes the motor switches Rf'3|, R-32 andRf-33 to/ establish the supply circuit for the motors. Relay R--S alsocompletes a holding circuit or itself independent of the starting switchby closing a switch R-34.

A motor M-3 driving a coolant pump (not shown is also started at thistime by momentary actuation of a switch S-6.- This switch completes acircuit for a relay R-ll whichr closes switches R'-4I, R-42 and Rf`43 toconnect the mot'or'M-S tothe power line. The relay also establishes aholding circuit for-itself by'closing a'switchAR-IIL f ltfwillfbeunderstoodthat a honing operation maybe-performed with' the'honerotating in either-direction- The direction of yrotation is determinedby the setting of a manually operable double pole switch S-'l arrangedto connect one ofthe-other of the running relays MF or MR' in thecontrol circuit. As shown, the switch is set `to connect up the forwardrunning relay MF.

When the machine isV to perform an ordinary honing operation, selectorswitches S-'-l, S'-2 ands- 3 are set in the -positionrshown in Fig. 4 ofthe drawings. i With switch S-l closed, actuation of the starting switchS-5 results in the energization ofthe relay R-I which shunts theresistances IR, 2-R'- and 3R from the supply circuitv of -the spindledriving motor. Relay R-I alsoprepares a holding circuit for the selectedrunning relay by closing aswitch R-I4 and interrupts the timerloperating circuit by opening a switch Rf--IiY i 4lAnvoperatingcycle'may'now be initiated by momentary vactuation of a cycle startingswitch S-S. Operation of this switch isusually effected by a manual`control member whichsimultane,- ously sets the control deviceslv'associated Iwith the'heaol reciprocating mechanism so as to initiateforward movement of the head.y Closure of the`fswitch S'-8.completes acircuit -Afor the selected runniri'glrelay; relay MF in the instantcase, which beoomesenergized and closes the the spindle motor M--2 in aforward direction. RelayMF also actuates the switch MF--4 to energizethe hone expansion solenoid `SO--I and initiate expansion ofthe hone asbefore explained.A Another switch MF-5, actuated by the relay MFcompletes a holding circuit for the relay inde- .pendent of the startingswitch.

trolling devices provided in honing machines of the type disclosed.During thiscycle, the honing tool is traversed repeatedly from one endof the work to the other in aworking stroke while the motor M--Zrotatesthe hone in timed relation to such reciprocation. To terminatethe cycle, the

action vofthe reciprocating controls are modied so as to eiTectwithdrawal of the hone from the Work and to stop the head in a withdrawnposition. The modication of the controls is eiected in well-known mannerby energization of a pullout solenoid S05-3. To energize the solenoid, aswitch S--Sis actuated manually or in any other suitable manner tocomplete a circuit for a control relay Rf-S which on energizing closes aswitch R-'SI to complete the circuit for the solenoid. AA switch S-I 0mechanically coupled with the switch S-9 opens the holding circuit forthe running relay MF to stop the spindle driving motor M-2 while thehone is being withdrawn. As the head 8 approaches its fully Withdrawnposition, the circuit of the relay R-5 is interrupted by the opening ofa limit switch I S-l thus permitting the control devices to return tomeans for relatively reciprocating the tool and work supports, anelectric motor operable to relatively rotate the tool and Work, meansoperable selectively to establish either a high voltage circuit or a loWvoltage circuit for said motor, a timing device, and means operablesimultaneously with said selectively operable means for placing the lowvoltage circuit under the control of said timer.

6. The combination in a honing machine having relatively rotatable andreciprocable tool and Work supports, of an electric motor operable toeffect the relative rotation of the tool and Work, control meansoperable selectively to establish either a high voltage or a 10W voltageoperating circuit for said motor, a brake actuating solenoid associatedwith said motor, a high voltage circuit for said solenoid, and a controlrelay connected in circuit with said motor and operable simultaneouslytherewith to control the solenoid circuit.

7. The combination in a honing machine having relatively rotatable andreciprocable tool and Work supports, of an electric motor operable toeffect the relative rotation of the tool and work, control meansoperable selectively to establish either a high voltage or a low voltageoperating current for said motor, a brake actuating solenoid associatedwith said motor, a high voltage circuit for said solenoid, a relay forcontrolling the solenoid circuit, a resistance coil, and switch meansoperable selectively to connect said relay to the motor circuit eitherdirectly or in series with said resistance coil' to enable the relay tofunction at either high or low voltage.

8. In a honing machine, in combination, a Work support, a support for anexpansible and contractible honing tool, an electric motor forrelatively reciprocating said support, a second electric motor forrelatively rotating the tool and Work, power actuated means forexpanding the tool, a solenoid controlling said poweractuated means, andswitch means operable to establish alternate energizing circuits forsaid solenoid, one of said circuits being closed only when both of saidmotors are running and the other of said circuits being closed when oneof the motors is running.

9. In a machine of the class described, in combination, a support for acylindrical abrasive tool, a support for Work to be operated on by thetool, means operable to relatively reciprocate the tool and Work axiallyof the tool, a motor operable to rotate the tool about its axis, and

. a timing device operative automatically to start and stop said motorperiodically.

10. In a machine of the class described, in combination, a support for acylindrical abrasive tool, a support for Work to be operated on by thetool, means operable to relatively reciprocate the tool and Work axiallyof the tool, an electric motor operable to rotate said tool about itsaxis, a circuit for said motor, timer actuated con"tro1 device operativeto open and close said circuit intermittently, and means operative toquickly stop said motor upon the opening of said circuit.

EARNEST Y. SEBORG.

